Furnace



July 1, 1930. F. J. DROEGE v FURNACE FiledOct. 31, 1928 2 Sheets-Sheet 2Ida/gator By .Atmmey;

Patented July 1, 1930 UNITE1DYST"T S Faun mo g, or"? covm'eron, KENTUCKY1 FURNACE I Application filed October 31, 1928.; seriar Nb. 316,259.

19 temperaturesattainable, as well as better Fig.3;

maintenance for correct operation. during the llf610f the furnace. Otherobjects will appear in the course of the following 'description.

' I attain these objects by: the device illustrated, for example;v intheaccompanyingdrawings, in whichf Figure l is a partial longitudinalvertical section on-theplane of the line l-l of v Fig.2 is a partialplan view, partly in horizontalsection on the plane of the line 2-2 ofFig.1; r

Fig. 8 is .a verticalicrossseotion on the 25 plane of the line 3-3 ofFig. 1;

Fig. 4 is a partial perspectiveview showing the water-containing.cooling elements in full lines, the outlines ofthe furnace and the watersupply and discharge pipesbeing shownby.dottedlines; and p Fig. 5 is apartial ver'tical section corresponding to that of Fig. 1, showing amodification ofthe roofof the combustion chamber. v

' About one half ofthe' upper structure of an open-hearth regenerativefurnace is illus-. trated; part of the hearth 1, "its-front wall 2' withdoors3, its rearwall 2 I and its arched roof 4 and one of the,combustion chambers 5, being shown. As is; well knownin the art, thecomplete installation would include the continuation of the hearthstructure,

and, at the opposite side'of this',.a second chamber 5 and regenerativeapparatus unfor controlling the flow of airand gases so that eachchamber-5 alternately becomes the inlet-while the other 'beoornestheoutlet to the regenerative apparatus, inwnich apparatus, on the way tothe stack, these gases lment.

derall of these structures, including means heat the passages, whichupon alternation heat the airthatis admitted with the fuel.

.These other partsfare omitted because the combustion chamber?) at theopposite side will be understood to be identical with the one indicated,and the regenerative device of any approved construction and arrange- Atthe outer side .of the combustion chamber 5 is the fuel inletstructurefi, comprising a vertical flue 7 that leads up froma sourceoffuel supply, not shown, withthe horiis not afiected by my inventionand may be n V zontal nozzle 8 leading in from the upper end of the flue7 and opening into the chamber 5. This nozzle1 8 considerably wider thanthe flue 7 allowing the fuel tospread forwardly and backwardlyinitstravel'into the chamber 5 toward theair inlet structure 9 which arein the outer rearand'frontcor ners of the chamber 5, with vertical fines10 7 leading up from the air passages of theregenerative' apparatus andopening upward into the chamber 5 above thelevel of the top of the fuelinlet nozzle 8. The roof 11 of the chamber- 5 slopes downwardly andinward-1y jfrom'the side walls of the furnace, and the front and rearwalls 12 of they chamber 5 converge inwardly past the inner upper cornerof the bridge 13 which forms the 1 bottom of the chamber, sloping inwardfrom about the level of the bottom of the nozzle 8. Inward fromthis thebaffle 14 V 7 extends up toa considerable height to join theroof 11; thebottom edge; of this bafile being above the level of the inner corner ofthe bridge 13. The hearth roof 4: inclines up from the lower edgeoftheybatfle 14, v a

, hich edge is arched in conformity with the: arching-of this r'oof l. a

. Theresult'of. the above arrangement is i that the air streams from'theinlets 9 are deflected downwardly and toward the 'middle of thechamberjafter passing'upto the roof 11, thus meeting the fuel with awhirling or eddying motion'as the fuel comes up from and spreads tofrontandrear from the nozzle 8, as roughly. indicated in- Figs. :1' and2, where the light arrows indicate air streams and dark arrows indicatefuel streams. In addition to having the upright baffle 14 in place ofthe usual sloping roof next to the usual knuckle, the passage over thebridge 13 is preferably more con- ISO stricted than usual by carryingthis baffle down lower than is the usual knuckle; this constrictionadding to the effectiveness of mixture and combustion.

This bathing and constriction intensifies the heating and erosiveeffects of the burning mixture on the adjacent structures; and to makepractical my improvements to aid combustion as above described, Iprovide for cooling these structures. The fuel inlet 6 has a waterjacket'15 comprising n1emdefined between the lower and upper ledges,

while the tops of the upper ledges 18 and 21 are covered withsimilarmaterial 24 and .the inside of the arch 22 is lined with similarmaterial '25. The side wall 26 of the furnace forms the outer walls ofthe flue 7 and nozzle 8, as well as of the air I inlet flues 10;affording access to the lines Lil by knocking out portions of the wall26.

The brickwork or equivalent refractory material'formin g the air inletstructures 9 is carried over the top of the water cooling arch 22 of thefuel inlet nozzle 8. The water jacket thus cools the fuel inlet 6 onthree sides and its top, and, by its lateral portions 16 adjacent theair inlet flue walls, also cools these air inlets 9. Outwardly, theseinlet structures are cooled by the atmosphere sufiiciently.

To protect the inner upper corner of the bridge 13, a pipe 27 runsthrough the furnace from front to rear, embedded in the structure of thebridge 13 up close to said corner. The baffle 14 is made up of a waterjacket 28 with its top edge horizontal and its lower edge arched andforming the lower edge of the baffle as before described, and with itsends communicating with upright water chambers 29 set against the frontand rear walls 2 and 2, respectively, of the furnace, and embedded inthe inner edges of the converging walls 12 of the combustion chamber 5;these chambers 29 resting upon the foundation of the furnace and thussupporting the baflie' The jacket 28 has the hollow ledge 30 along itsstraight top edge, and hollow ribs 31, 32 and 33 from this ledge 30 downto the lower edge; these ribs diverging upwardly and, with the led e 30,being on the side of-the jacket 28' acing into the chamber 5. Facings 34and 35 of brickwork-or the like are supported by these ribs and by theadjacent downwardly converging walls 12, and thus presented toward themixing fuel and air within the chamber 5. The roof 4 is cooled byelongated front to rear water jackets 36 shaped to conform with thearching of the roof over the hearth, and let into the brickwork thereofat suitable intervals, allowing increased tempera ture at the hearthwithout rapid deterioration of the roof 4.

By providing eifective cooling means for the bafile 14 and the bridge13, adjacent to the passage leading from the mixing chamher 5 to thehearth 1, the baffle 14 may be extended much lower than is the usualknuckle, without too rapid destruction of the bridge and bafflematerials. Thus, the passage may be constricted as much as may bedesirable for effective combustion, as an aid to the provisions foreffective mixing before described. The eifective cooling of the upperportions of the bafiie 14, as well as of the fuel and air inletstructures, prolongs the life of the mixingor combustion chamberstructures under the increased heat afforded by the above provisions. Byproper cooling, the design of the furnace may be maintained, whereasheretofore, erosion and fusing of the structural materials has madethisdifficult.

The various water jackets have watercir-' culated through them; anapproximate arrangement of piping for this purpose being indicated indotted lines in Fig. 4, where the main manifold pipe 37 has branches 38,39., 40 and 41 leading, respectively, to the inlet jacket 15, bridgepipe 27 baffle jacket 28, and hearth roof jackets 36, and outlet pipes42, 43, 44 and 45 lead, respectively, from these several coolingelements. Circulation through such a system may be maintained undergravity, or by suitable pumping apparatus, according to the amount ofwater required for cooling. This, of course, also will dictate therelative sizes of the jackets; and it will be understood that thecooling effect should not be such as to appreciably reduce thetemperature of the furnace gases, but only such as to avoid too rapiddeterioration of the furnace structure.

' In the modification shown in Fig. 5 the roof 11 ofthe mixing orcombustion chamber 5' is in the form of an approximately semicirculararch from front to rear, affording a higher space into which theincoming air may rise, producing a more marked eddy of the air downwardand forward in mixing with the fuel, aided by the baiile 14, which,with'the fuel and air inlets, as well as the other parts ofthe furnace,not shown, will be understood to be the same as in the example of Figs.1 to 4, inclusive. 7 It will be understood that natural or producer gasis the usual fuel, but that other fuels, such as oil or other liquidfuels, with suitable spraying devices, may be used, with correspondingchanges in the construction,

and that other modifications in proportions and arrangement, or' inapplication of cooling means, may occur- 1n difl'erent installations.

furnace, it is applicable to other metal treating apparatus, amon whichmay especially be mentioned soa ing pits of steel 7 plants. I do not.wish, therefore, to be understood as being limited to the precise dis-I closures herein, but having thus fully described an example of myinvention and its mode of operation, as is required, what I claim as newand desire to secure by Letters Patent is: a V

1. In a furnace, a hearth, a combustion chamber having a passage to saidhearth and having a fuel inlet and an-a'ir inlet, a baflle constrictingsaid passage and forming an upright wall of said chamber, facing saidinlets, a water. jacket comprised in said baffle, and water chambers atthe ends of said bafiie next to the walls of the furnace, communicatingwith said water jacket.

2; In a furnace, a hearth, a combustion chamber 'having'a passage tosaid hearth and having a fuel inlet and an air inlet, a bafiieconstricting said passage and 001m prising a water jacket havingupwardly diverging ribs facing said inlets, and refractory materialsupported by said ribs.

3. In a furnace, a hearth, a combustion chamber comprising an outer sidewall, a

, the respective corners of said outer side, wall and the front and rearwalls, openingv front wall and a rear wall, air inlets near upwardly, afuel inlet near said outer" side wall and between said air inlets,opening toward said hearth below the airinlet openings, said combustionchamber having a bottom extending from said air and fuel inlets towardsaid hearth and having a roof above the upward openings of'saidairinlets, and having a bafile wall next to said hearth, extending downin said hearth close I to the hearth end of said bottom of saidcombustion chamber and extending upright to said roof, above the levelof said air inlet openings, whereby air from said air inlets rises tosaid roof and is deflected thereby toward said baflie wall and isdeflected downward by said bafiie wall to strike substantiallyvertically upon the fuel coming from said fuel inlet to mix with saidfuel a in the space between said inlet and said baffle wall, over saidbottom of said combustion chamber, before entering said hearth belowsaid bafile'wall.

V FRED J. DROEGE.

Also, while the invention is illus-' trated as applied to an open hearthmelting

